The former president called the Senate minority leader “third rate” and “one of the most unpopular politicians in the United States.”
The Senate leader was assured by Jared Kushner that the former president would "bow to reality" and concede, according to the report.
Republican leaders in Congress will reportedly attend church with Biden instead of witnessing Trump's formal send-off at Joint Base Andrews.
The Senate trial will help write one of the final chapters of the majority leader's legacy.
The New York Times reported that the Senate majority leader privately believes the president committed impeachable offences.
"Republican party must finally learn to fight," Trump tweeted, one day after the Senate majority leader finally acknowledged Joe Biden and Kamala Harris' win.
The Senate majority leader congratulated the president-elect on Tuesday after weeks of refusing to acknowledge President Donald Trump's loss.
The Senator majority leader is called out for failing to pass additional relief measures to help Americans struggling through the pandemic.
The US Senate majority leader said Obama was "classless" for criticising Trump.
The former US president calls for "better policy decisions" on dealing with the coronavirus pandemic.